Follow the money and all radical Islamist roads lead back to Saudi Arabia
It's customary to open the first speech of a conference with the catch-all welcome of "Good morning, ladies and gentlemen". It's more of a habit than anything else. It is therefore unusual to then look down more carefully from the podium at the huge hall and realise that there are no ladies present at all.
This absence was one of my first impressions of Saudi Arabia and, although it should have been expected, addressing an all-male audience - many in dresses - in this day and age, feels extremely backward. If a country is trying to be a leading global power and economic giant, excluding half its population seems a bit daft.
That's Saudi Arabia and I was in its main city, Riyadh.
In contrast, last year at a similar event in Morocco, it couldn't have been more different. In Morocco, the hall is full of women, they are vocal and questioning, and in Casablanca there is a sense of equality - or at least something moving towards equality. In Saudi, the opposite is the case. Let's just say that you'd be waiting a while in Riyadh for a #wakingthefeminists Twitter handle!
The difference between both countries and between Saudi Arabia and many other Sunni Muslim countries is that Saudi Arabia has embraced Wahhabism. When I was in Riyadh, I spoke to a few Arab friends to try to get a handle on Wahhabism because, if you want to understand the region, it's critical to understand this strain of Islam that is preferred by - and exported by - Saudi Arabia.
You can't understand Isil and what drives them to blow up ancient Roman, Persian and Buddhist monuments without understanding Wahhabis. Nor can you understand what perverted logic drives them to kill innocents without learning about this type of strict Islam.
Muhammad ibn Abd al Wahhab was born not far from Riyadh in 1703. He trained as a holy man and was, like many religious people, constantly torn between a purist adherence to the original scriptures and a more tolerant accommodation of the word of God leavened with the reality of day-to-day living. This schism is not unusual. The fight between puritanism and pragmatism is after all, at the heart of the great split in the western Christian Church too - what we call the Reformation.
Al Wahhab called for the purification of Islam and a return to pristine Islam. When the young Imam called for the beheading of women in his local town for adultery, the people knew this guy meant business. However, it is likely that this form of extremism wouldn't have caught on in what was, by the standards of the time, a reasonably tolerant place had it not been for local insurrection against the unpopular Ottoman Empire which ran the Arabian Peninsula and taxed the locals mercilessly.
Possibly in an effort to get God on his side in his fight against Istanbul, the local leader of a small oasis, Mohammad ibn Saud, threw his lot in with the renegade preacher, Al Wahhab, in 1745. The link between the House of Saud and Wahhabi was forged there and then; and they have been allies ever since.
At the time, Islam, like lots of religions, was a concoction of bits of other religions, beliefs and practices. These had been borrowed and customised along the way. Remember this part of the world was the crucible of civilisation, the epicentre of the world's great trading routes and a place where the three main monotheist religions, Christianity, Judaism and Islam had been founded - Judaism and Christianity literally a few yards from each other, Islam a few hundred miles down the road.
Given this mix, it's hardly surprising that there were huge overlaps in these faiths and, as Islam was the newest creed, it borrowed the most. Al Wahhab objected to this evolutionary, almost 'hand-me-down' approach to Islam. As a purist, he wanted to go back to basics, to make pristine the religion. Possibly the most important tenet of Wahhabis is that they believe in what they call "the oneness of God". As a result, association with lesser gods, other gods, mysticism, shrines, temples, saints or holy men amounts to idolatry and must be stamped out.
This put Wahhabis on a collision course with the other strains of Islam such as Shi'as or, even worse in the eyes of the Wahhabis, Sufism. Shi'as and Sufis were the enemy within and, of course, Judaism and Christianity were the enemies at the door. Wahhabis called for jihad against all these infidels.
The Saudi/Wahhabi alliance was cemented by war and conquest as Arabian armies, immersed in a pure sectarian Islam, rampaged around the southern flanks of the crumbling Ottoman Empire. The Wahhabis were feared, deploying extremely brutal tactics against their Shi'ite enemies, for example in their sacking in the early 19th century of Karbala, Mecca and Medina, which were particularly vicious. But just in case we Christians get on our high horse, such sectarian savagery was a re-run of the earlier, 17th century, Thirty Years War in Europe.
For a century, the march, and reach, of the Wahhabis was limited to the Arabian Peninsula. Then the game changed, Saudi Arabia struck oil and the politics of the region altered forever, so too did geo-politics and Western economic expedience. Once the Saudis discovered oil, the West snuggled up to Riyadh, no questions asked.
Now the most extreme form of Islam was wedded to the richest country on earth and the Saudis have set about exporting not just oil, but a radical, intolerant form of Islam which drives Isil and various other jihadi groups. Saudi Arabia has spent some of its vast oil wealth on financing madrassas from Malaysia to Manchester - some of which are projecting Wahhabi ideas far from the Gulf.
Isil, with its murder of innocents, its desecration of ancient monuments and its subjugation of women, is the latest incarnation of extreme Wahhabism, and Saudi Arabia - the West's biggest ally in the region - is Isil's biggest external financier.
It costs money to wage war and Isil gets money from oil, local racketeering, hostage-taking and external private donations. The private donations come from donors, many of whom are Saudi.
When you follow the money, all radical roads lead back to Saudi Arabia, not states that are supposedly the West's enemies such as Libya, Iraq or even Assad's Syria.
From the majority of the 9/11 hijackers, to Bin Laden, his al-Qa'ida chief lieutenants and now Isil, each of these extremist organisations are the 21st century offspring of Muhammad ibn Abd al Wahhab, the cleric who came out of the desert in the 1730s and the institution he allied with in 1745: the House of Saud.